GaN epitaxial layers grown by the solution-cast seed layer HVPE technique: Effect of reactor heating method on structural and optical quality

Thin high crystallinity GaN epitaxial layers were grown on (0001) Al2O3 substrates by solution-cast seed layer formation process using a precursor material, tris(N,N-dimethyl-dithiocarbamato) gallium(III) [(Ga(mDTC)3)]. The solution-cast seed layer formation process was found compatible with the modified hydride vapor phase epitaxy (HVPE) technique, when the reactor heating was properly managed. XRD and PL studies evidenced that the GaN growth with continuous ramp-up of reactor temperature produces highly crystalline GaN thin films with negligible defects at relatively lower growth temperature compared to other existing growth techniques and further simplifies the growth process.